Photocatalytic degradation of organic pollutants and detection of chemical oxygen demand by fluorescence methods

Abstract

TiO 2 photocatalyst was used to degrade organic pollutants in aqueous solutions and the detection of chemical oxygen demand was studied by fluorescence method. It was found that TiO 2 dosage, initial solution pH, initial concentration electron acceptor Ce 4+, the time of UV light irradiation and the temperature of solution affected the degradation of the organic pollutants. The optimum conditions were obtained at amounts of TiO 2 1.0 g l −1, pH 0.38, Ce 4+ 6.0 mmol l −1, time 10 min and temperature 80 °C, respectively. The produced Ce 3+ was determined by fluorescence method, with the maximum excitation and emission wavelengths at 264.8 and 362.1 nm, respectively. The fluorescence intensity was linear with COD in 0∼100.0 mg l −1. The limit of detection was 0.9 mg l −1. This method was applied in detection of COD in samples of lake water and simulate sewage.